The difference between the length of the bat (inches) and its weight (ounces)

Example: A bat that is 33 inches long and weighs 30 ounces has a length-to-weight ratio of -3. Every bat of that particular
model will have a length-to-weight ratio of -3 (e.g. 32 in/29 oz; 34 in/31 oz)

What is the maximum length-to-weight ratio allowable for College or High School Baseball?

As of 2001, the maximum length-to-weight ratio is -3 for college and high school baseball

Can a Bat be used for Softball and Little League, or Little League and Adult Baseball, or Softball and Adult Baseball?

No, each bat is specifically made for each sport or level of play. For instance, a Little League Bat cannot be used for
Softball. Each bat is labeled on the barrel indicating the sport/level with the weight and length

What is End Loading?

End Loading is usually found in softball bats. It means there has been some material added to the end of the bat barrel
to add weight and create more of an end-balanced bat. The "End Load" is usually a polyurethane material that fills approximately
1" - 4" of the barrel

There are varying views on performance enhancement -- in general, slow-pitch players like the weight on the end of the bats
to help move the sweet spot further out and create more momentum

What is Wall Thickness? Why do some bats say "Ultra-Thin Walls" on the barrel?

Performance in bats depends on three things, (besides the person swinging the bat)